[SOLVED] How to add an array of values to a Set

How to add an array of values to a Set

The old school way of adding all values of an array into the Set is:

// for the sake of this example imagine this set was created somewhere else 
// and I cannot construct a new one out of an array
let mySet = new Set()

for(let item of array) {
  mySet.add(item)
}

Is there a more elegant way of doing this? Maybe mySet.add(array) or mySet.add(...array)?

PS: I know both do not work

Solution

As of June 2024, the new Set methods are considered baseline, as they are now available on all major browsers, plus Node.js, Deno, and Bun.

This means that now there is a way that can be considered elegant, as well as functional, by using the Set.prototype.union() method:

const set = new Set(['a', 'b', 'c'])
const arr = ['d', 'e', 'f']
const extendedSet = set.union(new Set(arr));
// Set { 'a', 'b', 'c', 'd', 'e', 'f' }

It works by creating a Set from the array and then creating a new Set which is the union of the two (i.e. it contains elements which are in either or both of the initial Set and the Set created from the array).